godan verb (-ku), transitive verb
beat down prices; sell at a knockdown price
Used when someone aggressively bargains to lower a price, or when an item is sold at a heavily discounted price, often with a nuance of forcing the seller to accept a low price.
彼は中古車を売り叩かれてしまった。
He was forced to sell his used car at a knockdown price.
市場で値段を売り叩
It's common to beat down prices at the market.